The present invention refers to a method of and apparatus for conveying articles, especially intermediate layers from a magazine to a transport unit for elongated articles.
It is one object of the present invention to provide a method of and an apparatus for continuously conveying articles from a magazine to several depositing areas without requiring any interruption of the operation when recharging the magazine.
This object is realized by providing a conveyor cooperating with at least one magazine which contains the articles and releases the latter onto the conveyor at a loading area for transporting the articles in conveying direction from the loading area to a plurality of predetermined positions wherein the conveyor is advanced step-by-step at a step length s=b/(n-1) in which b is the distance between two adjacent positions and n is the number of positions. The articles are transported by respective lifting units which are arranged at each of the predetermined positions. The number of lifting units and thus of predetermined positions corresponds to the number of depositing areas.
Each lifting unit for the associated predetermined position includes a cylinder-piston arrangement whose piston rod supports an engaging member which during the upward displacement of the piston lifts the article from the position and deposits it onto the depositing area defined by a respective transfer arm of a transport unit. To allow each engaging member to move past the aligned transfer arm, all cylinders of the lifting units are commonly connected to a horizontal rod which is movable in horizontal direction to tilt the cylinders to one side.
Preferably, the conveyor is a conveying chain whose links are open to allow the engaging members to pass therethrough when moving up and downwardly. Each link is provided with a pocket to receive one article released from the magazine.
Aside from the uncomplicated mechanical structure for supplying the conveying chain with articles, there is the advantage that no complicated control mechanism is necessary for the supply of articles and no logic is required for reintroducing returned excess intermediate layers or articles obtained during the initial stage of the process or in case not all articles are lifted from their respective position e.g. in case of intermediate layers for elongated articles of short length. Without any additional expenditures, it is also achieved that a plurality of magazines is completely emptied even if not all lifting units are actuated.
Through the step-by-step movement of the conveyor, the articles can accurately be positioned on the conveyor and transported to the lifting units because the conveyor is not moved when the articles drop from the magazines and lifted therefrom. Through determining the step length in accordance with the invention, the acceleration of the conveyor during the transport of the articles is kept to a minimum but is still sufficient to guarantee the transport of the articles to the lifting units in a relatively short period. In a typical conveying apparatus, the available time is e.g. 10 seconds for 9 articles which are arranged over a length of 8 m.
The apparatus according to the invention does not require a complicated control mechanism and is reliable in operation. Since the magazines are laterally arranged next to the depositing areas i.e. transfer arms, free access to the magazines is provided so that an easy recharging without requiring to shut down the transport apparatus is provided.
The method and the apparatus are suitable for any kind of article but especially for the supply of intermediate layers to a transport unit for elongated articles. In addition, it should be noted that the apparatus can certainly be used in a reverse cycle which means to pick up articles from the depositing areas and to convey them to one or several magazines.